问题
选择题
当我们的肱二头肌和肱三头肌分别处于收缩和舒张状态时，表现出来的动作是（ ）
A．屈膝
B．伸膝
C．曲肘
D．伸肘
答案
答案：C
本题考查骨、关节和骨骼肌的协调配合。屈肘时，肱二头肌收缩，肱三头肌舒张；伸肘时，肱三头肌收缩，肱二头肌舒张。故选C。
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当我们的肱二头肌和肱三头肌分别处于收缩和舒张状态时，表现出来的动作是（ ）
A．屈膝
B．伸膝
C．曲肘
D．伸肘
答案：C
本题考查骨、关节和骨骼肌的协调配合。屈肘时，肱二头肌收缩，肱三头肌舒张；伸肘时，肱三头肌收缩，肱二头肌舒张。故选C。
Directions: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.
The speeches of US President Barack Obama have become the favorite way for Japanese to study the English language. Japanese publishers have been ____小题1: ____ the market with over a dozen language-learning titles. Companies are trying to tap into a foreign-language teaching ____小题2: ____ that the Yano Research Institute said was ____小题3: ____ at 767 billion yen ($8.6 billion) in 2008. Why is there such a massive Japanese market for recordings and books of Obama's speeches? Japanese say that listening to Obama speak is a sure-fire way to ____小题4: ____ their English-speaking skills. Most Japanese, including those studying English, would have difficulty ____小题5: ____ a speech given by a native English speaker. But “Obama's English is easy to understand because he can ____小题6: ____ words clearly and speaks at a relatively slow clip,” said Professor Tadaharu Nikaido, a communication specialist. “Movies ____小题7: ____ to be the most difficult for Japanese, especially when actors mumble their words.” Obama sets his ____小题8: ____ of vocabulary wide enough to accommodate all levels of English speakers, Nikaido added, and at the lower end, it sometimes comes within the range of non-native speakers' comprehension. The Obama speech phenomenon has given way to more books and magazines that focus on how Obama's communication skills might be ____小题9: ____ in Japan for business and political purposes. At least half a dozen books and magazine covers of this kind have appeared in the past several months in Japan. |